Recently, display panels for televisions with a higher resolution of 4k2k (3840×2160 pixels) have been introduced in the market, and the products such as 4k2k televisions are drawing more attention. The resolution of 4k2k has pixels four times as many as the resolution of Fill High Definition (Full HD) (1920×1080 pixels), and thus video containing a large amount of information can be output with a higher resolution than Full HD.
As a technique to transmit signals from a video output device to a video display device, a High-definition Multimedia Interface (HDMI) is used generally. In the HDMI, a video output device outputting video such as a DVD player acquires, from a video display device such as a television, extended display identification data (EDID), which is information indicating resolutions supported by the video display device, and determines a resolution based on the acquired EDID to perform output.
The HDMI standard defines available resolutions for outputting, and the latest HDMI standard (1.4b) also supports 4k2k video output. It has been possible recently to convert video data with a Full HD resolution into one with a 4k2k resolution to display the converted video clearly with a higher resolution.
When both the video output device and the video display device have a resolution conversion function for converting video data with a Full HD resolution into one with a 4k2k resolution, and their performance of resolution conversion function are different, the image quality of the video data varies depending on which performs resolution conversion, the video output device or the video display device.
However, the video output device conforming to the current HDMI standard acquires resolutions that can be received by the video display device from the EDID to perform output with a maximum resolution. Thus, for the video display device with a 4k2k resolution, the resolution of the video data is always converted into 4k2k by the video output device, which makes it difficult to display video data with image quality intended by the manufacturer of the video output device.